The invention is directed generally to a system for restraining freight, and more particularly, to a composite restraint system capable of restraining freight from movement during transportation that includes at least a strap and a tensioning tool.
Throughout history, society, has transported merchandise and personal effects from one locale to another for a variety of reasons. These items have been transported through a variety of transportation mechanisms including containers, such as trunks, baskets, suitcases, boxes, and numerous other custom shipping devices. As time has progressed and transportation modes, such as the automobile, train, airplane, and ship, have undergone dynamic changes in the name of efficiency and progress. Likewise, technology surrounding freight restraint systems has progressed in an effort to accommodate the increased rates of speed of transportation and the increased demands of the customers.
While large pieces of freight may be transported through many different methods methods, today it has become common to transport freight within intermodal containers or flat bed trailers. Intermodal containers typically are twenty to forty feet in length by eight to ten feet in width by seven to nine feet in height. Intermodal containers have become an integral part of the transportation industry because of their convenience and adaptability. Specifically, intermodal containers may be stacked upon each other on the deck of a cargo ship, mounted on wheel structures for land transportation, or mounted on flat deck train cars, thereby enabling intermodal containers to transport freight via land, sea, or rail.
While intermodal containers bridge the gap between transportation via land, sea or rail, the containers fail to provide adequate means for securing the pieces of freight located therein. Specifically, most freight possess exterior dimensions that do not make them readily available to be positioned tightly within the interior surfaces of an intermodal container. For instance, a typical twenty foot long intermodal container may hold eighty fifty-five gallon barrels double-stacked within its interior compartment. In this position, approximately one to two inches exist between the rearward-most surface of the freight and the interior surface of the doors. While this small amount of space appears to be insignificant and undeserving of attention, just the opposite is the case, primarily because of the importance of restraining freight from moving to prohibit damage and to comply with regulations, such as United States Federal Regulation 49 C.F.R. 176.76, Oct. 1, 2000, requiring that freight traveling by vessel be secured to prevent movement in any direction. Further, other regulations (like United States Federal Regulation 49 C.F.R. 176.834, Oct. 1, 2000), requires that hazardous materials transported on public highways be secured against movement.
When containers change direction or speed, the freight contained therein continue along the previously established path until contacting the interior surface of the container and thereby forcing it to change direction. Without some type of restraint or cushioning system, the freight builds up considerable momentum independent of the container. When the freight contacts an interior surface of the intermodal container, the momentum possessed by the freight creates a force that is absorbed by the freight. Such absorption of the force may damage the freight, the packaging surrounding the freight or the walls of the intermodal container. Damaging the shipping containers may cause a release of hazardous materials. Accordingly, it is undesirable to permit freight to gain momentum independent of the intermodal container.
The transportation industry has addressed this issue by attempting to restrict freight from moving by using numerous methods. For instance, freight has been secured through lumber bracing and load-locking. Load-locking freight entails placing wood between the rear doors of the intermodal container and the freight and between the sides of the intermodal container and the freight. Typically, construction of the wood bracing is not performed by employees of the transporter; rather, the construction is outsourced to carpentry crewsxe2x80x94a process that has proven to be costly and time inefficient. Further, wooden supports are often brittle and unable to absorb the forces developed during transportation. Additionally, as loads shift during transit, bracing often falls from its position to the floor and is rendered useless. Moreover, traditional load-locking using lumber bracing is not capable of being used for all freight. For instance, positioning eighty fifty-five gallon drums within a typical intermodal container does not allow enough space between the rearward surface of the drums and the interior surface of the doors of the intermodal container. Thus, the method of load-locking using lumber bracing is fraught with shortcomings.
Another attempt of restraining freight is disclosed within U.S. Pat. No. 4,264,251. The 251 patent discloses an invention which is composed of sealing strips that are adhered to opposing sides of a container, a strip of bracing material and an adjoining mechanism used to bind the ends of the strips together into a secure and taut restraint. The disclosure of this patent is hereby incorporated into this application by reference.
While the 251 patent solved some of the problems associated with the previous methods employed for bracing freight, it did not solve all of the problems and at times created other problems. For instance, the 251 patent discloses a method of securing freight within an intermodal container by applying strips of material to the walls of the intermodal container using an adhesive that is applied separately. Installation of these strips of material is labor intensive and costly as regulation of the amount of adhesive placed on each strip is not easily controlled. Further, the juncture where the strips contact one another provide an opportunity for slippage because of inherent weakness in the design. Moreover, these strips of material are prone to elongate when subject to a force. Specifically, these strips are prone to elongating about 23 percent when subjected to a force, as evidenced by testing conducted by the Bureau of Explosives and reported in the Bureau""s Intermodal Loading Guide, Circular No. 43-C, Pamphlet No. 45, BOE Pamphlet No. 6C, Last Revised March 1998 (hereinafter, BOE Pamphlet).
An additional disadvantage of the prior art is that the tools used to secure the strips of material around a load of freight require two or more people to use. Typically, the tools include a cylindrical shaft having a slot for receiving the material. The tool is used to tighten strips of material around a load of freight by first positioning ends of the material within the slot. The tool is then rotated using a wrench. A ratchet holds the tool in this position and prohibits it from unwinding during the tightening process. Thus, the ratchet allows the tool to be rotated but prevents it from unwinding. Typically, a head of the ratchet is attached to the tool at a first end, and a second end of the ratchet, located opposite the first end, is positioned so that it bears against the freight. In this position, a single person can tighten the strips of material around the load of freight. However, a single person cannot attach a patch over the intersection between the two strips of material because as the ratchet bears against the load of freight after the material has been tightened, the forces generated by the tool and translated to the ratchet arm cause the tool to be pushed away from the freight. As a result, a second person is needed to push the tool in contact with the freight while another person affixes a patch across the intersection.
Thus, a need exists for a device capable of restraining freight during transportation from movement in all directions and capable of being attached to a variety of surfaces. Further, a need exists for a device having the ability to return to its original shape and location after absorbing a force. In addition, a need exists for a restraint system which employs an efficient method of using restraint straps. Finally, a need exists for a tool capable of being used by a single person to tighten strips of material around freight and to affix the strips in this position.
Set forth below is a brief summary of the invention that solves the foregoing problems and provides benefits and advantages in accordance with the purposes of the present invention as embodied and broadly described herein. This invention is directed to a composite restraint system capable of restricting freight from movement in all directions during transportation via ship, land, or rail. The composite restraint system includes a composite restraint strap, a composite restraint patch and a tensioning tool. In addition, the composite restraint system includes a strap having a pre-attached patch. In another embodiment, the invention includes a composite restraint strap having at least one pre-attached reinforcement strap.
The composite restraint strap is composed of at least two layers. A first layer is composed of a high strength yarn which has a certain percentage of recovery and elongation. A second layer preferably includes spunbonded fibers. The yarn forming the first layer is typically adhered to the second layer using an adhesive. Each strand of yarn is adhered to the second layer parallel to the longitudinal axis of the second layer. The composite restraint patch is composed of materials capable of restraining the strap during use.
The composite restraint strap may be adhered to a floor of a transportation device using an adhesive that is capable of adhering to unclean surfaces composed of materials including, but not limited to, painted surfaces, fiberglass, plastics, metals, and wood. In one embodiment of the composite restraint system, a composite restraint strap is used to restrain a load of freight by first adhering the composite restraint strap to the floor of the transportation device. The freight is placed on top of the restraint strap and each end of the restraint strap is brought over the freight. In this position, the strap contacts each side of the freight and the ends of the strap overlap. A tensioning tool is used to tighten the composite restraint strap around the freight by rotating an end of the strap around a body having at least one slot for receiving the strap. The tensioning tool is rotated using a wrench, ratchet, or some other tension arm. Once taut, a patch is placed over the overlapping ends of the composite restraint strap. The patch may be composed of materials such as a woven fabric, a nonwoven fabric, or the composite material set forth above. The patch prevents the first and second ends of the composite restraint strap from substantial movement relative to each other through the use of a permanent-type pressure sensitive adhesive. After the patch has been installed over the intersection between the first and second ends of the composite restraint strap, the tensioning tool is removed from its position on the composite restraint strap.
In another embodiment, the patch is pre-attached to an end of the composite restraint strap before installation around freight. In this embodiment, the strap may be a Woven fabric, a non-woven fabric or a composite material as set forth above. The patch may be attached to the end of the strap prior to use of the strap to make it easier for personnel to install and tighten the strap around freight. In this embodiment, the patch is attached to the strap at a contact section.
Connecting the composite restraint patch to the composite restraint strap before application simplifies the installation process. In particular, the individual installing the composite restraint does not have to first adhere a patch to the first end of the strap. Instead, the patch has already been attached to the strap. This feature greatly reduces that probability of ruining a patch before it is used.
In another embodiment, a patch is not necessary to secure a strap around a load of freight. Instead, a first end of the strap can be secured to an opposite end using adhesives placed on the first end. In this embodiment, an adhesive can be applied to the first end before or during installation. If applied before installation, a releasable film can be used to prevent the adhesive from adhering to items unintentionally.
In addition to restraining freight from vertical movement by securing freight to the floor of a transportation device, the composite restraint strap may restrain freight from lateral and longitudinal movement by securing the freight to the side walls of the transportation device. In this application, a composite restraint strap is adhered to side walls of the transportation device through an adhesive capable of adhering to surfaces such as, but not limited to metal, wood, plastics, fiberglass, and painted surfaces. The composite restraint strap may include an adhesive on one surface of the strap together with a releasable film to protect the adhesive from adhering to surfaces or itself prior to being installed on the side wall of the transportation device. Installation of the strap proceeds in the same fashion as described above.
This invention also includes a mechanism for tightening the straps described above around a load of freight. This mechanism is a tensioning tool that includes a body having at least one slot for receiving a strap and a clamp having clamp arms for receiving another end of a strap. The tool permits a single person to tighten at least one strap around a load of freight because the clamp arms hold one end of the strap while the other end is tightened around the outside surface of the body of the tool. Specifically, the clamp arms of the clamp hold one end of a strap using a cam mechanism that holds the arms tight against each other. While the clamp holds one end of a strap, the other end is inserted into a slot within the body of the tool and rotated until tight, Once tight, the strap is held in this position using a patch or another end of the strap described above, and the tool is removed. Thus, a single person can install the straps described above without assistance from another individual.
In another embodiment of the invention, the composite restraint strap can further include at least one reinforcement strap. The reinforcement strap can be positioned generally parallel to a longitudinal axis of the composite restraint strap and can be attached to an edge of the composite restraint strap. During use, the reinforcement strap can be attached with another end of a reinforcement strap using a buckle.
This invention aims to achieve at least one of the following advantages:
An advantage of this invention is that the composite restraint strap possesses a small percentage of creep after elongation that prevents the composite restraint straps from becoming slack due to over-elongation after absorbing a force during use.
Another advantage of this invention is that the small amount of creep eliminates the need for tape or other means for securing restraint straps in place to avoid sagging of the restraint straps in the event that the pieces of freight are compressed during transportation. In other words, many straps known in the art require that pieces of tape be used to hold a strap in position in the event that the strap elongates and fails to recover, thereby forming slack in the strap. This fact is evidenced by the BOE Pamphlet that describes loading procedures and states that strapping should be taped to the intermediate bulk containers to prevent sagging if it becomes slack in transit. Without the pieces of tape in position on the strap, the strap would fall out of position In contrast, the small amount of creep inherent within the instant invention eliminates this need to hold the strap in position. This advantage reduces the material costs involved with shipping freight, reduces labor costs associated with placing pieces of tape on the straps, and reduces the cost of replacement of freight damaged as a result of straps sliding off of the cargo.
Yet another advantage of this invention is that the composite restraint strap may be positioned around certain goods so that only select goods may be removed at a certain delivery location without having to re-secure the freight remaining within the container that is to be delivered at another location.
Still another advantage of the present invention is that the dimension of the composite restraint strap is typically less than the width of the straps previously used in the transportation industry, thereby reducing costs and making installation and storage easier.
Yet another advantage of the present invention is that the composite strap system requires less material and less adhesive to properly secure freight because the strap is smaller in size and the adhesive is more efficiently positioned on each strap based on each customer""s requirements.
Still another advantage of the present invention is that the non-releasable adhesive used together with the patch holds the straps together with greater strength. Further, the non-releasable adhesive does not release the two straps when subjected to an impact as happens with the adhesives previously used.
Yet another advantage of the present invention is that the strength of the composite restraint strap may be increased or decreased according to the customer or industry requirements by changing the denier of the fiber used without changing the performance of the belt. Building the strap to accommodate a particular anticipated load leads to cost savings on raw materials and manufacturing costs.
Still another advantage of this invention is the ability to restrain freight from moving in all directions in compliance with United States regulations.
Yet another advantage of the present invention is that freight may be restrained from vertical movement resulting from harmonic vibrations created in trailers used on the highway or created by road obstructions, such as potholes or speed breakers.
Still another advantage of the present invention is that the adhesive allows the composite restraint straps to be fastened to steel, wood, plastics, fiberglass, painted surfaces, and unclean surfaces.
These and other features and advantages of the present invention will become apparent after review of the following drawings and detailed description of the disclosed embodiments.